CAMRT Radiography Practice Exam

Which projection of the knee provides a more detailed view of the joint space?

1. AP medial oblique

2. AP upright

3. Lateromedial

4. Seated tangential

The correct answer is: AP upright

The AP upright projection of the knee is particularly useful for evaluating the joint space because it allows for a more accurate representation of the anatomy in a weight-bearing position. When patients are upright, the effects of gravity on the joint structure are evident, leading to a clearer assessment of the alignment and any potential pathologies, such as osteoarthritis. In this position, the joint space can be assessed more effectively as the femoral condyles and tibial plateau are better visualized under load, which can highlight narrowing of the joint space or any abnormalities that may not be as apparent in other projections. This projection also reduces the possibility of superimposition of surrounding structures, providing a cleaner image to analyze the knee joint itself. Additionally, the upright position contributes to a more functional view of the knee, as it simulates everyday activities, further enhancing the diagnostic value of the images. Other projections may not provide the same level of detail regarding the joint space due to differences in positioning or lack of weight-bearing conditions.